Lesson video

Hi, I'm Mr Chan, and in this lesson we're going to learn how to convert fractions to decimals and percentages by using a calculator.

Let's begin with this example.

We're going to use a calculator to convert five eighths to a decimal and a percentage.

So here's what your calculator display may look like.

So, there should be a fraction button on your calculator, so let's press that, and the fraction appears on your display.

We're going to put five into the numerator, press the down button to get into the denominator and enter eight in there.

So we get the fraction displayed on our calculator, and if we press the equals button, we should get the decimal value 0.

625.

If you calculator still displays the fraction however, there is a button you can press that converts that to a decimal, which is the hold the SD button, scientific to decimal notation.

Another way to think about the fraction five eighths, is it's simply five divided by eight, so we can enter that into our calculator as five divined by eight.

So we also then press equals, and it would again display the decimal equivalent 0.

625.

So that's pretty straightforward.

So now we know five eighths on our calculator equals 0.

625.

Now, to get that to a percentage we simply multiply by 100.

So we take the answer and multiply by 100, so your calculator may have an answer button which we can use, and press equals, that gives us 62.

5, and that's the fraction as a percentage.

So now use your calculator to help you convert these fractions to decimals and percentages.

Pause the video to have a go, resume the video once you're finished.

Here are the answers.

Now some of these questions you may not need a calculator to actually work these out because some of these you may already know, for example three fifths I know is 0.

6 already.

It's one of those that I already know.

So if you did use a calculator for any of these questions, I wonder which method you preferred.

Did you use the fraction button to help you convert these to decimals and percentages, or did you simply use the division method as outlined in the examples.

So let's see if you can match up these cards.

There are equivalent fraction, decimal and percentage cards.

Match those up, have a go, pause the video to have a go at this, resume the video once you're done.

Here are the answers.

So hopefully you managed to match up all of those cards correctly, remember you can use the fraction button on your calculator to change the fraction into a percentage, or simply enter the numerator, divide it by the denominator, and then from the decimal you can multiply by 100 to get that value into a percentage.

Here's another question for you to try.

Pause the video to complete the task, resume the video once you're finished.

Here are the answers.

So you'll realise sometimes that percentages are not whole numbers, and that's the reason why, that when you convert the fraction into a fraction out of 100, the numerator isn't always a whole number, so percentages sometimes don't always end up being a whole number either.

Here's another question for you to try.

Pause the video to complete the task, resume the video once you're finished.

Here are the answers.

So in this question, it's broken into two parts.

It's asking you firstly what the percentage attendance is for each class.

So it's only given you the number of pupils absent, so you could work that out, and then subtract that from 100%, or you could figure out how many pupils were present, knowing how many pupils were absent, because the percentage attendance calculates how many pupils were actually present.

So for example in class X, there were 26 pupils present because three pupils were absent out of the 29.

So the percentage attendance would be calculated as 26 out of 29, and you can use your calculator to help you with that percentage.

That's all for this lesson, thanks for watching.